Magnetic memory device

Abstract

A magnetic memory device includes: a first magnetic layer having a fixed magnetization direction; a layer containing a predetermined element, comprising at least one predetermined element selected from bismuth (Bi), antimony (Sb), and tellurium (Te); a second magnetic layer disposed between the first magnetic layer and the layer containing the predetermined element, wherein the second magnetic layer has a variable magnetization direction; and a first non-magnetic layer disposed between the first magnetic layer and the second magnetic layer. The second magnetic layer includes: a first layer portion having a (100) crystal orientation; and a second layer portion disposed between the layer containing the predetermined element and the first layer portion, wherein the second layer portion has a (110) crystal orientation.

Description

Technical Field

[0001] The embodiments described herein are generally related to a magnetic memory device. Prior Technology

[0002] A magnetic memory device has been proposed that integrates a plurality of magnetoresistive elements on a semiconductor substrate. Summary of the Invention

[0003] An embodiment provides a magnetic memory device comprising a magnetoresistive effect element having one of the advantageous properties.

[0004] According to an embodiment, a magnetic memory device includes: a first magnetic layer having a fixed magnetization direction; a layer containing a predetermined element, comprising at least one predetermined element selected from bismuth (Bi), antimony (Sb), and tellurium (Te); a second magnetic layer disposed between the first magnetic layer and the layer containing the predetermined element, wherein the second magnetic layer has a variable magnetization direction; and a first non-magnetic layer disposed between the first magnetic layer and the second magnetic layer. The second magnetic layer includes: a first layer portion having a (100) crystal orientation; and a second layer portion disposed between the layer containing the predetermined element and the first layer portion, wherein the second layer portion has a (110) crystal orientation. Simple Explanation of the Diagram

[0005] Figure 1 is a schematic cross-sectional view illustrating a basic configuration of a magnetic memory device according to one of the first embodiments. Figure 2 is a schematic cross-sectional view illustrating one of the basic configurations of a modified version of the magnetic memory device according to the first embodiment. Figure 3 is a schematic cross-sectional view illustrating a basic configuration of a magnetic memory device according to a second embodiment. Figure 4 is a schematic cross-sectional view illustrating a basic configuration of a first modified scheme of the magnetic memory device according to the second embodiment. Figure 5 is a schematic cross-sectional view illustrating a basic configuration of a second modified version of the magnetic memory device according to the second embodiment. Figure 6 is a schematic cross-sectional view illustrating a basic configuration of a third modification of the magnetic memory device according to the second embodiment. Implementation

[0006] The embodiments will be described below with reference to the figures.

[0007] First Embodiment Figure 1 is a schematic cross-sectional view illustrating a basic configuration of a magnetic memory device according to one of the first embodiments.

[0008] The structure illustrated in Figure 1 is disposed on a lower structure (not illustrated) comprising a semiconductor substrate and serves as a magnetoresistive element. Specifically, the magnetoresistive element serves as a magnetic tunneling junction (MTJ) element exhibiting perpendicular magnetization.

[0009] The magnetic memory device of the first embodiment illustrated in Figure 1 includes a reference layer 10 as a magnetic layer, a storage layer 20 as a magnetic layer, a tunneling barrier layer 30 as a non-magnetic layer, a shift elimination layer 40 as a magnetic layer, an intermediate layer 50 as a non-magnetic layer, and a layer 60 containing predetermined elements. The magnetic memory device has a multilayer structure in which these layers 10 to 60 are stacked one on top of the other.

[0010] More specifically, the reference layer 10, storage layer 20, tunneling barrier layer 30, and intermediate layer 50 are disposed between the offset elimination layer 40 and the layer 60 containing predetermined elements. The storage layer 20 is disposed between the reference layer 10 and the layer 60 containing predetermined elements, the tunneling barrier layer 30 is disposed between the reference layer 10 and the storage layer 20, and the intermediate layer 50 is disposed between the reference layer 10 and the offset elimination layer 40.

[0011] The reference layer 10 is a ferromagnetic layer with a fixed magnetization direction and exhibits perpendicular magnetization. That is, the magnetization direction of the reference layer 10 is perpendicular to the upper or lower surface of the reference layer 10. The reference layer 10 contains at least one element selected from iron (Fe) and cobalt (Co), and may further contain boron (B). In the first embodiment, the reference layer 10 is formed of a CoFeB layer containing Co, Fe, and B.

[0012] The storage layer 20 has a ferromagnetic layer with a variable magnetization direction and exhibits perpendicular magnetization. That is, the magnetization direction of the storage layer 20 is perpendicular to the upper or lower surface of the storage layer 20. The storage layer 20 includes a first layer portion 21, a second layer portion 22, and a third layer portion 23.

[0013] The first layer portion 21 contacts the tunneling barrier layer 30 and has a (100) crystal orientation parallel to either the upper or lower surface of the first layer portion 21. As used herein, having a "(100) crystal orientation" means including a crystal structure oriented in the (100) plane. That is, the lower and upper surfaces of the first layer portion 21 are oriented in the (100) plane. The first layer portion 21 contains at least one element selected from iron (Fe) and cobalt (Co), and may further contain boron (B). In a first embodiment, the first layer portion 21 is preferably formed of a CoFeB layer containing all of Co, Fe, and B.

[0014] The second layer portion 22 is disposed between the layer 60 containing the predetermined element and the first layer portion 21, contacts the layer 60 containing the predetermined element, and has a (110) crystal orientation. As used herein, having a "(110) crystal orientation" means having a crystal structure oriented in a (110) plane. That is, the lower and upper surfaces of the second layer portion 22 have a (110) crystal orientation. The second layer portion 22 contains at least one element selected from iron (Fe) and cobalt (Co). In a first embodiment, the second layer portion 22 may be formed from a CoFe layer containing either Co or Fe.

[0015] The third layer 23 is disposed between the first layer 21 and the second layer 22, and contacts both the first layer 21 and the second layer 22. The third layer 23 is disposed between the first layer 21 and the second layer 22 to separate the first layer 21 and the second layer 22. Separating these layers makes it possible to clearly distinguish the orientation of the first layer 21 as the (100) plane and the orientation of the second layer 22 as the (110) plane. The third layer 23 is also disposed in this way to facilitate the orientation of the second layer 22 in the (110) plane.

[0016] The third layer 23 is made of a material containing (1) at least one element selected from ruthenium (Ru), platinum (Pt), iridium (Ir), palladium (Pd), rhodium (Rh), silver (Ag), and gold (Au) or (2) an amorphous magnetic material. As an amorphous magnetic material, for example, a material containing one of cobalt (Co), zirconium (Zr), and niobium (Nb) (CoZrNb) or a material containing one of cobalt (Co), zirconium (Zr), and molybdenum (Mo) (CoZrMo) can be used.

[0017] The tunneling barrier layer 30 is an insulating layer and is formed of an MgO layer containing magnesium (Mg) and oxygen (O). The tunneling barrier layer 30 has a crystal orientation (100) parallel to the upper or lower surface of the tunneling barrier layer 30. That is, the lower and upper surfaces of the tunneling barrier layer 30 are oriented in a plane (100) that is the same as the orientation of the first layer portion 21 of the storage layer 20.

[0018] The offset elimination layer 40 is a ferromagnetic layer with a fixed magnetization direction and exhibits perpendicular magnetization. That is, the magnetization direction of the offset elimination layer 40 is perpendicular to the upper or lower surface of the offset elimination layer 40. The offset elimination layer 40 has the function of eliminating a magnetic field applied from the reference layer 10 to the storage layer 20, and the magnetization direction of the offset elimination layer 40 is antiparallel to the magnetization direction of the reference layer 10. The offset elimination layer 40 has a superlattice crystal structure in which cobalt (Co) and platinum (Pt) are stacked alternately on top of each other.

[0019] The intermediate layer 50 is formed of an iridium (Ir) layer or a ruthenium (Ru) layer, and the reference layer 10 and the offset elimination layer 40 are coupled together via the intermediate layer 50 to form an antiferromagnetic coupling (SAF coupling).

[0020] A layer 60 containing a predetermined element is disposed on the storage layer 20 and serves as a top cover layer. The layer 60 containing the predetermined element contains at least one predetermined element selected from bismuth (Bi), antimony (Sb), and tellurium (Te). That is, the layer 60 containing the predetermined element may be formed from a Bi layer that substantially contains only Bi, an Sb layer that substantially contains only Sb, or a Te layer that substantially contains only Te. Alternatively, the layer 60 containing the predetermined element may be formed from a layer that substantially contains one or more elements selected from Bi, Sb, and Te. In addition to at least one predetermined element selected from Bi, Sb, and Te, the layer 60 containing the predetermined element may further contain other elements. In the first embodiment, the layer 60 containing the predetermined element is formed from a Bi layer, an Sb layer, and / or a Te layer.

[0021] As used herein, "substantially contains" or "substantially constitutes" means that a small amount of an element other than a given element (e.g., other than one of Bi, Sb, or Te) is permitted to be included in a layer containing that given element. The same applies to the description below.

[0022] In the first embodiment, the layer 60 containing predetermined elements is configured such that the vertical magnetic anisotropy of one of the storage layers 20 is increased and a magnetoresistive effect element with one of the advantageous properties is obtained. An explanation of such advantageous properties will now be given.

[0023] In order to obtain a magnetoresistive element with advantageous properties, the perpendicular magnetic anisotropy of the storage layer 20 is increased. However, as the size of the magnetoresistive element decreases, it becomes more difficult to obtain a storage layer 20 exhibiting high perpendicular magnetic anisotropy.

[0024] In the first embodiment, a layer 60 containing predetermined elements, formed of a Bi layer, an Sb layer, and / or a Te layer, is disposed adjacent to the storage layer 20. Bi, Sb, and Te exhibit strong spin-orbit coupling, and the Bi layer, Sb layer, and / or Te layer being disposed adjacent to the storage layer 20 increases the magnetic anisotropy of one interface of the storage layer 20.

[0025] In the case where the Bi layer, Sb layer and / or Te layer are disposed adjacent to one of the storage layers 20, the storage layer 20 is oriented in the (110) plane to exhibit high perpendicular magnetic anisotropy. However, in order to obtain favorable tunneling magnetoresistance (TMR) properties, the storage layer 20 is oriented in the (100) plane at least near an interface between the storage layer 20 and the tunneling barrier layer 30, wherein the tunneling barrier layer 30 is oriented in the (100) plane.

[0026] In the first embodiment, the first layer portion 21 of the storage layer 20 has a (100) crystal orientation parallel to the upper or lower surface of the first layer portion 21. The second layer portion 22 of the storage layer 20 has a (110) crystal orientation. Therefore, in the first embodiment, the first layer portion 21 ensures high TMR, and the second layer portion 22 increases vertical magnetic anisotropy. That is, the first layer portion 21 adjacent to the tunneling barrier layer 30 ensures high TMR, and the second layer portion 22 exhibiting high vertical magnetic anisotropy increases the overall vertical magnetic anisotropy of the storage layer 20.

[0027] Using a layer 60 containing at least one predetermined element selected from Bi, Sb and Te usually yields advantages similar to those described above.

[0028] In the first embodiment, the third layer portion 23 is disposed between the first layer portion 21 and the second layer portion 22, such that the orientation direction of the first layer portion 21 and the orientation direction of the second layer portion 22 are effectively distinguished from each other. That is, the first layer portion 21 is oriented in the same (100) plane as the tunneling barrier layer 30, and the second layer portion 22 is oriented in the (110) plane, thereby achieving high vertical magnetic anisotropy based on the layer 60 containing predetermined elements.

[0029] To obtain the structure described above, a preliminary multilayer structure is first formed, having layers corresponding to layers 10 to 60 of the multilayer structure illustrated in Figure 1. In this preliminary multilayer structure, a region corresponding to the first layer portion 21 of the storage layer 20 is in an amorphous state. That is, in this preliminary multilayer structure, boron is uniformly distributed over the entire region corresponding to the first layer portion 21, and therefore, the region corresponding to the first layer portion 21 is in an amorphous state. The layer structure in this preliminary multilayer structure, except for the region corresponding to the first layer portion 21, is similar to the layer structure in the multilayer structure illustrated in Figure 1. In this preliminary structure, the crystal orientation of the second layer portion 22 differs from that of the first layer portion 21, which is attributed to the insertion of the third layer portion 23.

[0030] Due to heat treatment of this initial multilayer structure, boron diffuses outward in the region corresponding to the first layer portion 21, and the region corresponding to the first layer portion 21 changes from an amorphous state to a crystalline state. Specifically, the first layer portion 21 becomes oriented in the same (100) plane as the tunneling barrier layer 30. Thus, the multilayer structure illustrated in FIG1 is obtained.

[0031] Figure 2 is a schematic cross-sectional view illustrating one of the basic configurations of a modified version of the magnetic memory device according to the first embodiment.

[0032] The basic structure of this modified scheme is similar to that of the first embodiment. In the first embodiment, the magnetoresistive element system is configured such that the storage layer 20 is a top-free magnetoresistive element above the reference layer 10; however, in this modified scheme, the storage layer 20 is a bottom-free magnetoresistive element below the reference layer 10. Therefore, the stacking order of layers 10 to 60 in this modified scheme is reversed compared to that in the first embodiment. Furthermore, in this modified scheme, layer 60 containing predetermined elements is used as a lower layer.

[0033] As described above, the basic structure of this modified solution is similar to that of the first embodiment, and the modified solution also obtains advantages similar to those of the first embodiment.

[0034] Second Embodiment Next, a magnetic memory device according to a second embodiment will be described. The basic components are similar to those in the first embodiment, and the description of these basic components described in the first embodiment will be omitted.

[0035] Figure 3 is a schematic cross-sectional view illustrating a basic configuration of a magnetic memory device according to a second embodiment.

[0036] As in the first embodiment, the structure illustrated in FIG3 is disposed on a lower structure (not illustrated) including a semiconductor substrate and serves as a magnetoresistive element. As in the first embodiment, the magnetoresistive element is an MTJ element exhibiting vertical magnetization.

[0037] As in the first embodiment, the magnetic memory device of the second embodiment illustrated in FIG3 includes a reference layer 10, a storage layer 20, a tunneling barrier layer 30, an offset elimination layer 40, an intermediate layer 50, and a layer 60 containing predetermined elements. The magnetic memory device has a multilayer structure in which these layers 10 to 60 are stacked one on top of the other.

[0038] More specifically, the reference layer 10, storage layer 20, tunneling barrier layer 30, and intermediate layer 50 are disposed between the offset elimination layer 40 and the layer 60 containing predetermined elements. The storage layer 20 is disposed between the reference layer 10 and the layer 60 containing predetermined elements, the tunneling barrier layer 30 is disposed between the reference layer 10 and the storage layer 20, and the intermediate layer 50 is disposed between the reference layer 10 and the offset elimination layer 40.

[0039] The basic configuration of the reference layer 10, the tunneling barrier layer 30, the offset elimination layer 40 and the intermediate layer 50 is similar to the basic configuration of the first embodiment.

[0040] The storage layer 20 contacts the tunneling barrier layer 30 and the layer 60 containing predetermined elements, and includes a layer portion having a (100) crystal orientation parallel to the upper or lower surface of the layer portion. That is, the storage layer 20 includes a layer portion oriented in a (100) plane. This layer portion oriented in a (100) plane contacts the tunneling barrier layer 30. The layer portion oriented in a (100) plane contains at least one element selected from iron (Fe) and cobalt (Co), and may further contain boron (B). In a second embodiment, the layer portion oriented in a (100) plane is preferably formed of a CoFeB layer containing Co, Fe, and B. Furthermore, in the second embodiment, the entire storage layer 20 is formed of the layer portion oriented in a (100) plane.

[0041] A layer 60 containing predetermined elements is disposed on the storage layer 20 and serves as a top cover layer. The layer 60 containing predetermined elements contains (1) at least one first predetermined element selected from bismuth (Bi), antimony (Sb), and tellurium (Te), (2) at least one second predetermined element selected from magnesium (Mg), titanium (Ti), zirconium (Zr), hafnium (Hf), scandium (Sc), yttrium (Y), aluminum (Al), silicon (Si), cerium (Ce), plutonium (Pr), samarium (Sm), thorium (Gd), tbium (Tb), and dysprosium (Dy), and (3) oxygen (O). In addition to the at least one first predetermined element, the at least one second predetermined element, and oxygen, the layer 60 containing predetermined elements may further contain other elements.

[0042] In the second embodiment, the layer 60 containing the predetermined element includes a portion substantially formed of the at least one first predetermined element, the at least one second predetermined element, and oxygen (O). In the second embodiment, the entire layer 60 containing the predetermined element is substantially formed of the at least one first predetermined element, the at least one second predetermined element, and oxygen.

[0043] Specifically, the layer 60 containing the predetermined element may be formed from at least one first predetermined element, at least one second predetermined element, and a compound containing oxygen. The layer 60 containing the predetermined element may have a structure in which the at least one second predetermined element is added to one of the at least one first predetermined element and one of the compounds containing oxygen, or it may have a structure in which the at least one first predetermined element is added to one of the at least one second predetermined element and one of the compounds containing oxygen.

[0044] As described above, in the second embodiment, the layer 60 containing predetermined elements is configured to obtain a magnetoresistive effect element with one of the advantageous properties. An explanation of such advantageous properties will now be provided.

[0045] As already explained, Bi, Sb, and Te, used as the first predetermined elements, exhibit extremely high spin-orbit coupling. Therefore, the layer 60 containing the first predetermined element is positioned adjacent to the storage layer 20, thereby increasing the vertical magnetic anisotropy of the storage layer 20.

[0046] However, elements exhibiting large spin-orbit coupling (the first predetermined element, such as Bi, Sb, or Te) typically exhibit a large spin-pumping effect. Therefore, in a comparative example where the layer 60 containing the predetermined element is formed from a layer containing only the first predetermined element, a damping value increases, and the reversal current of the magnetoresistive effect element (the current required to reverse the magnetization direction of the storage layer 20) increases.

[0047] Layer 60 containing a predetermined element is formed from an oxide layer containing a first predetermined element and oxygen, thereby reducing the damping value and the reversing current of the magnetoresistive element. However, without the addition of a second predetermined element, the coupling between the first predetermined element and oxygen is weak and therefore unstable. When the second predetermined element is added, the resulting coupling between the first and second predetermined elements and oxygen is stable. Specifically, in a comparative example where the second predetermined element is not added, the oxygen contained in layer 60 containing the predetermined element couples to boron that diffuses outside the storage layer 20. Therefore, in this comparative example, a large amount of oxygen in layer 60 containing the predetermined element has combined with boron, and for this reason, the coupling between the first predetermined element and oxygen is difficult to exist stably in layer 60 containing the predetermined element. Therefore, the advantage of reduced damping value obtained by the coupling between the first predetermined element and oxygen is weakened.

[0048] In the second embodiment, in addition to the first predetermined element and oxygen, the layer 60 containing the predetermined element further contains a second predetermined element. The coupling between the second predetermined element and oxygen is stronger than the coupling between boron and oxygen. Therefore, in the second embodiment, the coupling between boron and oxygen is reduced. Thus, in the second embodiment, the first predetermined element and oxygen are stably present in the layer 60 containing the predetermined element, and the damping value is sufficiently reduced.

[0049] As explained above, in the second embodiment, a layer 60 containing a first predetermined element, a second predetermined element, and oxygen is provided. Therefore, the vertical magnetic anisotropy of the storage layer 20 is increased; the damping value is sufficiently reduced by improving the stability of the layer 60 containing the predetermined elements; and the increase in the reverse current is effectively minimized. Thus, a magnetoresistive element with advantageous properties is obtained.

[0050] Figure 4 is a schematic cross-sectional view illustrating a basic configuration of a first modified scheme of the magnetic memory device according to the second embodiment.

[0051] The basic structure of the first modified embodiment is similar to that of the second embodiment. In the second embodiment, the magnetoresistive element system is configured such that the storage layer 20 is a top-free magnetoresistive element above the reference layer 10. In the first modified embodiment, the storage layer 20 is a bottom-free magnetoresistive element below the reference layer 10. Therefore, the stacking order of layers 10 to 60 in the first modified embodiment is the reverse of that in the second embodiment. Furthermore, in the first modified embodiment, layer 60 containing predetermined elements is used as a lower layer.

[0052] As described above, the basic structure of the first modified scheme is similar to that of the second embodiment, and the first modified scheme also obtains advantages similar to those of the second embodiment.

[0053] Figure 5 is a schematic cross-sectional view illustrating a basic configuration of a second modified version of the magnetic memory device according to the second embodiment.

[0054] The basic structure of the second modified embodiment is similar to that of the second embodiment. The layer 60 containing predetermined elements contains at least one first predetermined element, at least one second predetermined element, and oxygen (O). As the at least one first predetermined element and the at least one second predetermined element, elements similar to those described above in the second embodiment are used.

[0055] In the second modification, the layer 60 containing a predetermined element includes a layer portion 61 containing at least one of the first predetermined elements and oxygen (O). The layer 60 also includes a layer portion 62 containing a second predetermined element disposed between the storage layer 20 and the layer portion 61 containing the first predetermined element. The layer portion 62 containing the second predetermined element contains at least one second predetermined element and oxygen (O). Specifically, the layer 60 containing the predetermined element includes (1) a layer portion 61 substantially formed of the at least one first predetermined element and oxygen (O), and (2) a layer portion 62 substantially formed of the at least one second predetermined element and oxygen (O). That is, an oxide incorporating the first predetermined element is used as the layer portion 61 containing the first predetermined element, and an oxide incorporating the second predetermined element is used as the layer portion 62 containing the second predetermined element.

[0056] As described above, the basic structure of the second modification is similar to that of the second embodiment, and the second modification also obtains advantages similar to those of the second embodiment.

[0057] Specifically, the layer portion 61 containing the first predetermined element increases the vertical magnetic anisotropy of the storage layer 20 and minimizes the increase in one of the reversal currents. The layer portion 62 containing the second predetermined element reduces the stability degradation of the layer 60 containing the predetermined element due to, for example, the diffusion of boron.

[0058] In cases where the layer portion 62 containing the second predetermined element is too thick, the advantage of the layer portion 61 containing the first predetermined element in enhancing the perpendicular magnetic anisotropy of the storage layer 20 is weakened. For this reason, the thickness of the layer portion 62 containing the second predetermined element is preferably less than the thickness of the layer portion 61 containing the first predetermined element. For example, the thickness of the layer portion 62 containing the second predetermined element can preferably be approximately equal to the thickness of a monolayer of the compound of the second predetermined element and oxygen.

[0059] Figure 6 is a schematic cross-sectional view illustrating a basic configuration of a third modification of the magnetic memory device according to the second embodiment.

[0060] The basic structure of the third modification is similar to that of the second embodiment and the second modification. In the second modification, the magnetoresistive element system is configured such that the storage layer 20 is a top-free magnetoresistive element above the reference layer 10. In the third modification, the storage layer 20 is a bottom-free magnetoresistive element below the reference layer 10. Therefore, the stacking order of layers 10 to 60 in the third modification is the reverse of the stacking order of layers 10 to 60 in the second modification. Furthermore, in the third modification, layer 60 containing predetermined elements is used as a lower layer.

[0061] As described above, the basic structure of the third modification is similar to that of the second embodiment and the second modification. The third modification also obtains advantages similar to those of the second embodiment and the second modification.

[0062] The first and second embodiments have been described above, but the configurations of the first and second embodiments can be combined. For example, the configuration of the layer 60 containing predetermined elements in the second embodiment can be applied to the layer 60 containing predetermined elements in the first embodiment. In this case, for example, the layer 60 containing predetermined elements is formed such that the percentages of the at least one first predetermined element, the at least one second predetermined element, and oxygen (O) are adjusted to obtain a second layer portion 22 oriented in the (110) plane as described in the first embodiment.

[0063] While specific embodiments have been described, these embodiments are presented by way of example only and are not intended to limit the scope of this disclosure. In fact, the novel embodiments described herein can be embodied in many other forms; furthermore, various omissions, substitutions, and changes can be made to the forms of the embodiments described herein without departing from the spirit of this disclosure. The accompanying claims and their equivalents are intended to cover such forms or modifications that fall within the scope and spirit of this disclosure.

[0064] Cross-reference to related applications This application is based on and claims priority to Japanese Patent Application No. 2024-041923, filed on March 18, 2024, the entire contents of which are incorporated herein by reference.

[0065] 10: Reference Layer / Layer 20: Storage layer / layer 21: First layer 22: Second layer 23: Third layer 30: Tunneling barrier layer / layer 40: Offset Removal Layer / Layer 50: Intermediate layer / layer 60: Layers / layers containing predefined elements 61: Layer containing the first predetermined element 62: Layer containing the second predetermined element

Claims

1. A magnetic memory device, comprising: A first magnetic layer having a fixed magnetization direction; A layer containing a predetermined element, comprising at least one predetermined element selected from bismuth (Bi), antimony (Sb), and tellurium (Te); a second magnetic layer disposed between the first magnetic layer and the layer containing the predetermined element, wherein the second magnetic layer has a variable magnetization direction; and a first non-magnetic layer disposed between the first magnetic layer and the second magnetic layer, wherein the second magnetic layer comprises a first layer portion having a (100) crystal orientation, and a second layer portion disposed between the layer containing the predetermined element and the first layer portion, the second layer portion having a (110) crystal orientation; wherein the second magnetic layer further comprises a third layer portion disposed between the first layer portion and the second layer portion, the third layer portion being made of a material containing (1) at least one element selected from ruthenium (Ru), platinum (Pt), iridium (Ir), palladium (Pd), rhodium (Rh), silver (Ag), and gold (Au) or (2) an amorphous magnetic material; The amorphous magnetic material is selected from (1) a material containing one of cobalt (Co), zirconium (Zr) and niobium (Nb) and (2) a material containing one of cobalt (Co), zirconium (Zr) and molybdenum (Mo).

2. The magnetic memory device of claim 1, wherein the first layer portion of the second magnetic layer contains at least one element selected from iron (Fe) and cobalt (Co).

3. The magnetic memory device of claim 2, wherein the first layer portion of the second magnetic layer further contains boron (B).

4. The magnetic memory device of claim 1, wherein the second layer portion of the second magnetic layer contains at least one element selected from iron (Fe) and cobalt (Co).

5. The magnetic memory device of claim 1, wherein the first layer portion of the second magnetic layer contacts the first non-magnetic layer.

6. The magnetic memory device of claim 1, wherein the second layer portion of the second magnetic layer contacts the layer containing the predetermined element.

7. The magnetic memory device of claim 1, wherein the layer containing the predetermined element is formed of (1) a bismuth (Bi) layer that substantially contains only bismuth (Bi), (2) an antimony (Sb) layer that substantially contains only antimony (Sb), or (3) a tellurium (Te) layer that substantially contains only tellurium (Te).

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